The reply to my query about an ore sorter was that it was...

The reply to my query about an ore sorter was that it was currently (March 2018) unfeasible since their multiple copper species and gold is more complex to identify and isolate; their high throughput of about 800-1000 tonne per hour is currently beyond the technology; and the short mine life materially impacts the capital return on investment. However, they were continuing to monitor the scalability and effectiveness combination with interest

Of note, a gold company that is just starting to use their ore sorter (cost about $2m installed), estimates that their AISC will reduce by about $150 per oz gold, once the sorter and some other associated improvements including of course a much increased annual mill production from 55,000 to 80-100,000 oz pa has occurred by the end of 2018. Of note, until recently this company was paying off a gold loan to CBA of about $2m or so every 3 months, so the ore sorter could easily be paid off by end of June.

Interestingly, as previously mentioned on this forum, this gold company estimates that the cost of haulage from their potential future gold mines about 60-70km away is relatively insignificant and will only increase their AISC by about $10 per oz, of gold. In my opinion this may not necessarily be the same for HGO since the concentration and relative sale price for copper is much less than for a gold mine.
HOWEVER, am I right in postulating that HGO may potentially change and become a gold mine in the future, with copper cost offsets? !! From my reading of the geology presentation and the HGO potential distant sites. And the postulated changes in geology as one moves further away from the open pit to the south east. Depending upon future drilling results of course. And any information on the recently purchased exploration areas of course.